The goal of this Phase I SBIR application is to develop a new minimally invasive therapy for laser ablation of epileptogenic seizure foci. There is a large unmet need for better treatment options for the nearly one million epilepsy patients in the U.S. that are refractory to current medical treatments. While surgical removal of the epileptogenic foci offers relief in 70 percent of the well selected cases, most patients decide against this option due to the highly invasive nature of the procedure. We hypothesize that precise, image-guided laser thermal ablation of epilepsy foci would provide results approaching surgical resection in terms of seizure relief, and could be carried out with a far lower risk of surgical morbidity to the patient. In Phase I we will use our FDA-cleared technology (Visualase Thermal Therapy System), which is currently used for cancerous tumor ablation applications, to perform a pilot feasibility study in adult epilepsy patients who are refractory to medical therapy and have an identifiable lesion deemed responsible for their seizures. We will also develop hardware and software enhancements which will optimize the system for this application. In Phase II, we will perform expanded multi-center clinical studies on patients with broader inclusion criteria, including treatment of mesial temporal lobe epilepsies. Finally, we will construct a data registry with the goal of gathering clinical data necessary for the design of a successful definitive FDA trial in Phase III in which we will seek specific indications for the treatment of Epilepsy. PUBLIC HEALTH RELEVANCE: RELEVANCE Current medical therapy leaves 30 percent of Epilepsy patients without adequate control of their seizures. Development of a minimally invasive surgical option for thermally destroying the tissue in the brain responsible for seizures would have a significant impact on epilepsy patients and their families. This project will develop precise methods using MRI-guided laser technology, which if successful, has potential to be that minimally invasive option.